n.1. a.  One that trims: a window trimmer.
b.  A device or machine, such as a lumber trimmer, that is used for trimming.
 2.  One who changes one's opinions, especially in politics, to suit the needs of the moment.
3.  Electronics   A variable component used to make fine adjustments to capacity or resistance.
4.  Architecture   A beam across an opening, such as a hearth, into which the ends of joists can be fitted.